mp4/mp4box/
hdlr.rs

1use byteorder::{BigEndian, ReadBytesExt, WriteBytesExt};
2use serde::Serialize;
3use std::io::{Read, Seek, Write};
4
5use crate::mp4box::*;
6
7#[derive(Debug, Clone, PartialEq, Eq, Default, Serialize)]
8pub struct HdlrBox {
9    pub version: u8,
10    pub flags: u32,
11    pub handler_type: FourCC,
12    pub name: String,
13}
14
15impl HdlrBox {
16    pub fn get_type(&self) -> BoxType {
17        BoxType::HdlrBox
18    }
19
20    pub fn get_size(&self) -> u64 {
21        HEADER_SIZE + HEADER_EXT_SIZE + 20 + self.name.len() as u64 + 1
22    }
23}
24
25impl Mp4Box for HdlrBox {
26    fn box_type(&self) -> BoxType {
27        self.get_type()
28    }
29
30    fn box_size(&self) -> u64 {
31        self.get_size()
32    }
33
34    fn to_json(&self) -> Result<String> {
35        Ok(serde_json::to_string(&self).unwrap())
36    }
37
38    fn summary(&self) -> Result<String> {
39        let s = format!("handler_type={} name={}", self.handler_type, self.name);
40        Ok(s)
41    }
42}
43
44impl<R: Read + Seek> ReadBox<&mut R> for HdlrBox {
45    fn read_box(reader: &mut R, size: u64) -> Result<Self> {
46        let start = box_start(reader)?;
47
48        let (version, flags) = read_box_header_ext(reader)?;
49
50        reader.read_u32::<BigEndian>()?; // pre-defined
51        let handler = reader.read_u32::<BigEndian>()?;
52
53        skip_bytes(reader, 12)?; // reserved
54
55        let buf_size = size
56            .checked_sub(HEADER_SIZE + HEADER_EXT_SIZE + 20)
57            .ok_or(Error::InvalidData("hdlr size too small"))?;
58
59        let mut buf = vec![0u8; buf_size as usize];
60        reader.read_exact(&mut buf)?;
61        if let Some(end) = buf.iter().position(|&b| b == b'\0') {
62            buf.truncate(end);
63        }
64        let handler_string = String::from_utf8(buf).unwrap_or_default();
65
66        skip_bytes_to(reader, start + size)?;
67
68        Ok(HdlrBox {
69            version,
70            flags,
71            handler_type: From::from(handler),
72            name: handler_string,
73        })
74    }
75}
76
77impl<W: Write> WriteBox<&mut W> for HdlrBox {
78    fn write_box(&self, writer: &mut W) -> Result<u64> {
79        let size = self.box_size();
80        BoxHeader::new(self.box_type(), size).write(writer)?;
81
82        write_box_header_ext(writer, self.version, self.flags)?;
83
84        writer.write_u32::<BigEndian>(0)?; // pre-defined
85        writer.write_u32::<BigEndian>((&self.handler_type).into())?;
86
87        // 12 bytes reserved
88        for _ in 0..3 {
89            writer.write_u32::<BigEndian>(0)?;
90        }
91
92        writer.write_all(self.name.as_bytes())?;
93        writer.write_u8(0)?;
94
95        Ok(size)
96    }
97}
98
99#[cfg(test)]
100mod tests {
101    use super::*;
102    use crate::mp4box::BoxHeader;
103    use std::io::Cursor;
104
105    #[test]
106    fn test_hdlr() {
107        let src_box = HdlrBox {
108            version: 0,
109            flags: 0,
110            handler_type: str::parse::<FourCC>("vide").unwrap(),
111            name: String::from("VideoHandler"),
112        };
113        let mut buf = Vec::new();
114        src_box.write_box(&mut buf).unwrap();
115        assert_eq!(buf.len(), src_box.box_size() as usize);
116
117        let mut reader = Cursor::new(&buf);
118        let header = BoxHeader::read(&mut reader).unwrap();
119        assert_eq!(header.name, BoxType::HdlrBox);
120        assert_eq!(src_box.box_size(), header.size);
121
122        let dst_box = HdlrBox::read_box(&mut reader, header.size).unwrap();
123        assert_eq!(src_box, dst_box);
124    }
125
126    #[test]
127    fn test_hdlr_empty() {
128        let src_box = HdlrBox {
129            version: 0,
130            flags: 0,
131            handler_type: str::parse::<FourCC>("vide").unwrap(),
132            name: String::new(),
133        };
134        let mut buf = Vec::new();
135        src_box.write_box(&mut buf).unwrap();
136        assert_eq!(buf.len(), src_box.box_size() as usize);
137
138        let mut reader = Cursor::new(&buf);
139        let header = BoxHeader::read(&mut reader).unwrap();
140        assert_eq!(header.name, BoxType::HdlrBox);
141        assert_eq!(src_box.box_size(), header.size);
142
143        let dst_box = HdlrBox::read_box(&mut reader, header.size).unwrap();
144        assert_eq!(src_box, dst_box);
145    }
146
147    #[test]
148    fn test_hdlr_extra() {
149        let real_src_box = HdlrBox {
150            version: 0,
151            flags: 0,
152            handler_type: str::parse::<FourCC>("vide").unwrap(),
153            name: String::from("Good"),
154        };
155        let src_box = HdlrBox {
156            version: 0,
157            flags: 0,
158            handler_type: str::parse::<FourCC>("vide").unwrap(),
159            name: String::from_utf8(b"Good\0Bad".to_vec()).unwrap(),
160        };
161        let mut buf = Vec::new();
162        src_box.write_box(&mut buf).unwrap();
163        assert_eq!(buf.len(), src_box.box_size() as usize);
164
165        let mut reader = Cursor::new(&buf);
166        let header = BoxHeader::read(&mut reader).unwrap();
167        assert_eq!(header.name, BoxType::HdlrBox);
168        assert_eq!(src_box.box_size(), header.size);
169
170        let dst_box = HdlrBox::read_box(&mut reader, header.size).unwrap();
171        assert_eq!(real_src_box, dst_box);
172    }
173}
mp4/mp4box/hdlr.rs

mp4/mp4box/
hdlr.rs
